Calutron assembling and disassembling apparatus



Jan. 27, 1959 R. E. ANDREWS 2,871,363

CALUTRON ASSEMBLING AND DISASSEMBLING APPARATUS Filed March 28, 1946 mvENIoR .ES Ram/v0 A/IDAfWS g BY flMW ATTORNEY.

United States PatentO CALUTRON ASSEMBLING AND DISASSEMBLING APPARATUS Roland E. Andrews, Watertown, Mass., assignor to the United States of America as represented by the United States Atomic Energy Commission Application March 28, 1946, Serial No. 657,636 6 Claims. (Cl. 250-413) The present invention relates to the art of treating a polyisotopic substance to produce a plurality of segregable masses wherein the distribution of the constituent isotopes has been altered so that one of the masses produced is enriched with respect to at least one isotope. The purpose of such treatment is to obtain a product characterized by an enhancement of the percentage of a selected isotope. More specifically, the invention relates to a device known in the art as a calutron, a term whose definition is any apparatus or machine where isotope separation or enrichment is achieved on a large scale yielding commercially useful quantities of one or more isotopes, by appropriate separative action on gaseous ions with electrostatic or electromagnetic means or combinations of them.

The foregoing definition has been taken from U. S. Patent No. 2,709,222, issued on May 24, 1955, to Ernest 0. Lawrence. In that patent, the theory of isotopic separation and the principles of operation of a calutron are fully set forth, and will not here be repeated.

It may be stated generally, however, that the calutron to which this invention relates comprises essentially an evacuated tank disposed in a strong, substantially uniform magnetic field, and a source and a receiver located within the tank.

The source includes an ionizing arc chamber having an electron emitting cathode associated therewith. The are chamber has an exit slit opening out into the tank, and spaced from the slit are two mutually spaced accelerating electrodes carried at a relatively high negative potential with respect to the arc chamber. As a result of this potential difference, positive ions formed in the arc chamber are drawn out through the slit, and are projected in a slightly divergent beam into the tank.

A continuous supply of material, the isotopes of which are to be separated, is provided in the arc chamber. This may conveniently be accomplished by providing a charge reservoir in communication with the arc chamber, and the material or a suitable compound thereof may be provided in the charge reservoir. The charge material may then be heated, and its vapor caused to flow at a controlled rate into the arc chamber, where ions of the several isotopes are formed and projected into the beam previously described.

The beam of positive ions of the polyisotopic substance is projected through the magnetic field in a direction 'normal to the field, and the beam is caused thereby to follow an arcuate path wherein the ions of the heavier isotope tend to concentrate in the region adjacent the outer periphery. From geometric considerations there results a substantial focusing of ions of the same isotope after approximately 180 of travel, and selective collection of isotopes may be made at this location.

Reference was previously made to the fact that the interior of the tank is evacuated. It has been found that best results are achieved when the tank pressure is on the order of 10- to mm. Hg. Due to the fact that the tank is evacuated, as described, it is necessary that Patented Jan. 27, 1959 the tank be of very massive construction to withstand the atmospheric pressure to which it is subjected.

In a practical embodiment of the present invention, the tank comprises a substantially rectangular vessel which has the following approximate dimensions: height twelve feet,.depth seven and one-half feet, and width two feet. The tank is open along one of its narrow edges and is closed by a removable face plate which is approximately two by twelve feet in size and weighs approximately 3500 pounds. The ion separating mechanism mounted on the face plate extends within the tank to a distance of approximately seven and one-quarter feet when the face plate is in position. This ion separating mechanism is relatively delicate, and great care must be exercised to prevent damage thereto during removal from the tank. Furthermore, the face plate is sealed to the tank, suitable sealing gaskets being employed, and the periphery is' tightly clamped to the edges of the tank opening by a plurality of bolts or clamping devices. It is therefore necessary to provide a support for the face plate which will sustain its weight and insure proper registry withthe tank opening while the bolts or clamping devices are engaged or disengaged.

With the foregoing general description in mind, it is an object of the present invention to provide face plate supporting means effective to hold the face plate in registry with the opening in the calutron tank during engagement and disengagement of the face plate securing means.

It is a further object of the present invention to provide a calutron having a face plate removably secured to the calutron tank and having means associated with the tank and face plate for preventing injury to the ion separating mechanism carried by the face plate, during insertion in and withdrawal from the tank.

More specifically, it is an object of the present invention to provide a calutron having a face plate adapted to close an open side thereof, in which the face plate is hinged adjacent the bottom of the tank in such a manner as to provide for guided withdrawal of the ion separating mechanism carried by the face plate.

A feature of the present invention is the provision of a spring-type hinge for the face plate which will prevent injury to the sealing gasket normally provided between the face plate and the tank.

A further feature of the invention is the provision of a hinged support for the face plate comprising readily separable hinge elements, so that the face plate may first be swung outwardly from its operative position far enough to clear the ion separating mechanism carried thereby, and may thereafter be elevated and transported by a conventional overhead crane.

A further feature of the invention is the provision of motor means, such as a piston and cylinder, operable to control swinging movement of the face plate into and out of closed relation against the side of the calutron tank.

Other objects will become apparent as the description proceeds, especially when taken in conjunction with the drawings, in which:

Figure 1 is a side elevation of a calutron tank with parts broken away;

Fig. 2 is a front elevation of the calutron tank showing portions of the adjacent electromagnets;

Fig. 3 is a detail view illustrating the connection between a piston rod and'the top of the tank face plate; and

Fig. 4 is a detail view, partly in section, of the hinge support for the face plate.

Referring now to Figs. 1 and 2, the calutron referred to is preferably arranged in a so-called racetrack, in which a plurality of tanks 10 are alternated between a series of erably being provided in the form of a closed geometriq figure so that there is a continuous path for magnetic flux through the series of tanks and magnets. A portion of the racetrack is indicated in Fig. 2, which shows a complete tank and indicates the relationship of the adjacent magnets in the series. This type of structure is illustrated and described in U. S. Patent No. 2,721,272, issued to Ernest 0. Lawrence, October 18, 1955.

Referring now specifically to Fig. 1, the tank 1% is substantially rectangular in shape, and has an open side at the right as shown in Fig. 1. The open side of the tank is adapted to be closed by the removable face plate 12, which is shown in closed position in full lines and in partially open positions in dot-dash lines in this figure.

Projecting inwardly from the face plate is an ion separating mechanism which comprises essentially a transmitter unit 13, a receiver unit 14, and a liner structure which interconnects the transmitter and receiver. in the embodiment illustrated, the transmitter 13 is a double transmitter having a pair of ion generating devices 16 which are associated with suitable accelerating mechanism, not shown in detail. For a detailed description of this type of ion separating mechanism, reference is made to U. S. Patent No. 2,714,664 to Ernest 0. Lawrence, which issued on August 2, 1955.

The receiver 14 is likewise a double receiver having a pair of pocket members 17, each of which is adapted to receive a selected portion of the beam transmitted from the corresponding transmitter element, all as described in the last mentioned patent.

The liner 15, which extends between the transmitter 13 and the receiver 14, is for the primary purpose of maintaining the beams between the transmitters and receivers in a substantially field-free space. As will be apparent from the drawing, the ion separating mechanism extends to a substantial depth within the tank when the face plate is in operative relationship thereto. The ion separating mechanism is relatively delicate, and during insertion in and removal from the tank, care must be exercised to avoid injury thereto. Since the face plate is a massive iron element weighing approximately 3500 pounds, it is essential that apparatus be provided to prevent injury to the ion separating mechanism which might otherwise result and to support the face plate during engagement and disengagement of the means securing the face plate to the calutron tank.

As best illustrated in Fig. 2, the face plate is secured to the tank by a plurality of individually removable clamping elements which are herein illustrated as bolts 19. It is apparent that because of the weight of the face plate, means must be provided effective to sustain the weight of the face plate, and more particularly to retain the face plate in accurate alignment with the open side of the tank, during removal and replacement of bolts 19.

In accordance with the present invention, the apparatus which supports the face plate and prevents injury to the ion separating mechanism takes the form of hinge means for the face plate which serves as a support and guide for the face plate during insertion in and removal from the calutrontank.

The face plate 12 is pivoted adjacent .its lower end to hinge structure shown in detail in Fig. 4. This hinge structure comprises essentially open-topped hinge elements 20, pivoted to a cross pin 21 which is supported at its ends by suitable means. As seen in Fig. 2, the

pin 21 may conveniently be supported at its ends by supporting elements 29 which are secured to appropriate portions of the electromagnets 11. The hinge elements have depending apertured cars 22, through which pass bolts 23 upon which are mounted compression springs 24 whose function is to retain the hinge elements 20 in the position shown in Fig. 4, while at the same time permitting slight movement thereof. Bolts 23 are mounted on brackets 25 which, as illustrated in Fig. 4, are secured adjacent the lower edge of the tank. It will be appreciated that when the face plate 12 is brought into substantial alignment with the opening in the tank 10, a slight further adjustment may be necessary to cause the bolts 19 to register exactly with the threaded sockets provided adjacent the edge of the opening in the calutron tank. This slight adjustment is permitted by the par ticular mounting of the hinge elements 20.

The face plate 12 is provided with forwardly extending flanges 26 adjacent its side edges which support a cross pin 27 at the bottom thereof. The cross pin 27 is of a size to be received within an open-topped socket portion 28 of the hinge elements 20. By virtue of this construction it will be apparent that the face plate 12 may be swung from the full-line position shown in Fig. 1 to a substantially horizontal position indicated in dot-dash lines in that figure, during which swinging movement the ion separating mechanism, including the source, liner, and receiver, are prevented from striking the side edges of the tank as a result of the guiding action of the supporting hinge structure. Furthermore, when the face plate 12 is in closing relation to the tank its weight is supported by the hinge structure while it is retained in accurately aligned relation so that the securing bolts 19 may be removed or replaced.

As will be apparent by an inspection of Fig. 1, the center of gravity of the assembly comprising the'face plate 12 and the ion separating mechanism, is located substantially within the tank when the face plate is in closing relation thereto. As a matter of fact, the center of gravity. is located at a position such that it will substantially overlie the hinge support when the face plate is swung outwardly approximately to the intermediate position indicated by dot-dash lines in Fig. 1. Consequently it is desirable to provide positive acting means for easing the face plate into fully closed relation to the tank, or for freeing the face plate and moving the same outwardly to a position where its center of gravity will cause it to swing freely forward to fully open position. For this purpose I have provided a piston and cylinder device indicated generally at 30, which is mounted for slight rocking movement about the pivot axis 31 formed by a cross pin mounted between the brackets on the top surface of the tank 10. A piston rod 32, shown in detail in Fig. 3, is provided at its outer end with a locking hook 33 provided with a spring-pressed locking pin 34. The vertically extending flanges 26, provided adjacent the edges of the face plate 12, support at their upper ends a cross pin 37 which cooperates with the hook 33. The slight rocking motion permitted the piston and cylinder by the pivot support 31 allows the piston and cylinder device to accommodate itself to the arcuate path traced by the upper edge of the face plate 12 during swinging movement of the face p ate.

Eyes 40 are provided at the top of the face plate for attachment to hooks 41 carried by cables 42 which are part of a conventional overhead hoisting arrangement;

The method of removing and replacing the face plate will now be traced in its entirety, assuming in the first place that the face plate is in closed relation and is tightly bolted to the tank by the plurality of bolts 19. At this time the bolts 19 may be removed and the weight of the face plate and the mechanism carried thereby will be sustained by the hinge elements 20. This will permit the complete removal'or freeing of the bolts 19, and the face plate will be retained in its closed position since the center of gravity lies inwardly of the hinge support. At this time the hooks 41 may be attached to the eyes 40 and slack taken up in the cables 42. Thereafter, fluid pressure is admitted to the cylinder of the piston and cylinder device 30 in a manner to cause the piston rod 32 to move outwardly from its cylinder. It may be that a considerable force is necessary to free the face plate from the tank, since it is sealed thereto by means including sealing gaskets 45 (Fig. 4) which may become frozen after a protracted period of use. When the face plate has been freed from the tank, it may thereafter be moved outwardly by the piston rod 32 until the center of gravity reaches and passes a position overlying the hinge support. Thereafter, the center of gravity tends to move the face plate outwardly and is further outward motion is restrained by the cables 42. As soon as the center of gravity has passed the axis of the hinge support and further motion is prevented by the cable 42, the hook 33 may be disengaged from the cross pin 37 and further movement of the face plate to substantially horizontal position may be controlled by paying out the cable 42, as will be apparent.

If desirable, downward swinging motion of the face plate 12 may be finally arrested by providing an abutment against which the upper edge of the face plate may eventually strike when the face plate reaches substantially horizontal position. Thereafter, other cables may be attached adjacent the lower edge of the face plate and it may be elevated and transported, as desired. It will be appreciated that so long as the cross pin 27 of the face plate remains engaged in the socket 28 of the hinge elements 20, the ion separating mechanism carried by the face plate is prevented from sideward movement which might cause injury thereto, and that when the face plate has reached substantially horizontal position, the ion separating mechanism is entirely clear of the tank walls.

In order to replace the face plate, it is brought into juxtaposition to the tank while in substantially horizontal position and the cross pin 27 is engaged in the socket 28 of the hinge elements 20. It is thereafter swung upwardly about its hinge axis to a position in which the hook 33 of the piston rod 32 may be engaged with the top cross pin 37. This will be done while the center of gravity of the face plate and the attached mechanism remains in the position to bias the face plate outwardly, as otherwise the face plate would slam against the tank. After the hook 33 has been engaged over the top cross pin 37, fluid pressure is admitted to the cylinder of the piston and cylinder device in a direction to urge the piston to the left, as seen in Fig. 1, so that the face plate 12 is brought firmly against the side walls defining the opening into the tank in a controlled manner. During this closing movement of the face plate, the hinge structure guides the face plate in a manner to prevent injury to the ion separating mechanism, and further insures that when the face plate engages the tank it is properly registered therewith so that the securing bolts 19 may be inserted and tightened. Any slight misalignment may be corrected, since the hinge elements are themselves pivoted so as to permit slight movement thereof.

While I have illustrated and described a preferred embodiment of my calutron structure, it will be appreciated that this has been done merely to permit those skilled in the art to practice the invention, the scope of which is indicated in the claims.

What is claimed is:

1. Calutron assembling and disassembling apparatus including a massive face plate adapted to be removably secured to a substantially fluid-tight calutron tank disposed between magnet pole faces and permeated with a strong magnetic flux, ion separating means carried by said face plate and projecting within said tank when said face plate is secured thereto, a sealing means interposed between said tank and said plate, hinge means supporting said plate upon said tank for movement of the ion separating means in a direction normal to said magnetic flux and pivot means for supporting said hinge means, said pivot means being supported by said magnet and providing a fulcrum axis for said hinge means substantially parallel to the direction of said flux.

2. Apparatus as defined in claim 1, wherein said hinge means comprises a plurality of separate hinges mounted in spaced relation upon said pivot means.

3. Apparatus as defined in claim 1, wherein said hinge means comprises a plurality of resilient separate hinges mounted in spaced relation upon said pivot means.

4. Apparatus as defined in claim 1, wherein said hinge means is mounted at the lower portion of said tank.

5. Apparatus as defined in claim 1, wherein said hinge means is mounted at the lower portion of said tank and the center of gravity of said plate and attached ion separating means lies inwardly of said fulcrum axis thereby to cause the assembled apparatus to assume a normally closed relationship.

6. In combination with an apertured stationary tank adapted to be evacuated and disposed between closely spaced magnet pole faces serving to permeate the tank with a strong magnetic flux, a calutron assembling and disassembling apparatus comprising, a movable closure for said tank aperture, a plurality of separate hinge means detachably pivoting said closure at its lower end upon a mounting supported by said pole faces, the axis of the fulcrum of said separate hinge means being substantially parallel to the direction of the magnetic flux, ion separating means supported by said closure and adapted to move into and from said tank in a direction substantially normal to said magnetic flux, a seal disposed adjacent the edge of said tank and adapted to be engaged by said closure during operation of said calutron, and actuating means detachably engaging said closure at a point removed from said hinge fulcrum thereby to effect respectively a gradual and controlledengagement and disengagement of said seal by said closure as said calutron is alternately assembled and disassembled.

References Cited in the file of this patent UNITED STATES PATENTS 

